'The Piano Guys' Make One Piano Sound Like a Symphony

Four musicians called The Piano Guys are known for their incredible covers and original songs, but it's this mindblowing cover of 'Angels We Have Heard on High' using a single piano that is going viral. Gillian Pensavalle (@GillianWithaG) has the video. You can watch more here: http://www.youtube.com/watch?v=n543eKIdbUI